International journal of antimicrobial agents
-
Int. J. Antimicrob. Agents · Jun 2011
Suppression of ciprofloxacin-induced resistant Pseudomonas aeruginosa in a dynamic kill curve system.
Current dosing approaches for treating microbial infections ignore resistant subpopulations. A clinical isolate of Pseudomonas aeruginosa was cultured in a dynamic in vitro kill curve system designed to simulate the half-lives of drugs in order to evaluate the drug-microbial response relationship. The first dose of ciprofloxacin (CIP) uses a concentration equivalent to the unbound fraction of a 200mg clinical dose. ⋯ The CIP MIC increased substantially from 0.13 μg/mL pre dose to 4 μg/mL at 12h after a CIP dose. In addition, aztreonam induced a similar resistance pattern as CIP, indicating that induction of resistance was not limited to fluoroquinolones. In conclusion, the in vitro dynamic kill curve system revealed that aminoglycosides, more than other classes of antibiotics, were effective against the CIP-induced resistant subpopulations.
-
Int. J. Antimicrob. Agents · Jun 2011
Pharmacokinetics of a loading dose of amikacin in septic patients undergoing continuous renal replacement therapy.
Data on the optimal amikacin regimen during continuous renal replacement therapy (CRRT) are scarce and the proposed loading dose of 10mg/kg may result in inadequate drug levels. The aim of this study was to describe the pharmacokinetics of a 25 mg/kg first dose of amikacin in septic shock patients treated with CRRT. Serum samples were collected before (t=0 h) and at 1 (peak), 1.5, 4.5, 8 and 24 h after a 30-min amikacin infusion in 13 consecutive patients treated with a combination of amikacin and β-lactam. ⋯ In septic shock patients treated with CRRT, a first dose of ≥ 25 mg/kg amikacin is therefore required to reach therapeutic peak concentrations. However, as drug clearance is reduced, amikacin concentrations remained above the threshold of renal toxicity at 24h. The therapeutic benefit of high-dose aminoglycoside therapy should be balanced with its potential renal effects in septic patients receiving CRRT.
-
Int. J. Antimicrob. Agents · Mar 2011
Meticillin-resistant Staphylococcus aureus (MRSA): screening and decolonisation.
Meticillin-resistant Staphylococcus aureus (MRSA) infections are of increasing importance to clinicians, public health agencies and governments. Prevention and control strategies must address sources in healthcare settings, the community and livestock. This document presents the conclusions of a European Consensus Conference on the role of screening and decolonisation in the control of MRSA infection. ⋯ The role of environmental contamination in MRSA infection is unclear, but screening may be helpful as an audit of hygiene procedures. In all situations, screening procedures and decolonisation carry a significant cost burden, the clinical value of which requires careful evaluation. European initiatives designed to provide further information on the cost/benefit value of particular strategies in the control of infection, including those involving MRSA, are in progress.
-
Int. J. Antimicrob. Agents · Mar 2011
Nationwide survey of antibacterial activity against clinical isolates from urinary tract infections in Japan (2008).
In this study, the causative bacteria and their sensitivity to various antimicrobial agents as well as risk factors for quinolone-resistant Escherichia coli were investigated in patients with acute uncomplicated cystitis or complicated cystitis by isolation and culture of bacteria from urine samples. In total, 1312 strains were isolated from 1009 patients with acute uncomplicated cystitis, including E. coli (63.3%), Enterococcus faecalis (12.8%) and Streptococcus agalactiae (4.6%). ⋯ Factors associated with quinolone-resistant E. coli included two or more episodes of cystitis within 1 year, failure of quinolone therapy, underlying urinary tract disease, prior quinolone treatment within 1 month and age ≥ 75 years. It is important to confirm the sensitivity of causative bacteria for optimal antimicrobial therapy, and empirical antimicrobial agents should be selected by considering patient characteristics and other factors.
-
Int. J. Antimicrob. Agents · Feb 2011
ReviewUpdate on screening and clinical diagnosis of meticillin-resistant Staphylococcus aureus (MRSA).
Based on the failure of conventional control strategies, some experts and public health officials have promoted active screening to detect asymptomatic carriers of meticillin-resistant Staphylococcus aureus (MRSA) as an effective prevention strategy. Data regarding the (cost-) effectiveness of MRSA screening have recently grown and have produced mixed results. Several clinical studies have not only provided conflicting findings but have also raised numerous issues about the appropriate populations for universal versus targeted screening, screening method(s) and intervention(s). ⋯ Results should be followed by appropriate interventions to reduce the risk of MRSA transmission and infection. We believe a reasonable approach in most European hospitals with an MRSA on-admission prevalence of <5% is to use targeted rather than universal screening (predominantly with chromogenic media, except for high-risk units and critically ill patients for whom molecular tests could be cost effective), after carefully considering the local MRSA epidemiology, infection control practices and vulnerability of the patient population. This strategy is likely to be cost effective if linked to prompt institution of control measures.